dolfinx.geometry

Methods for geometric searches and operations

Functions

compute_closest_entity(tree, midpoint_tree, ...)

Compute closest mesh entity to a point.

compute_colliding_cells(mesh, candidates, x)

From a mesh, find which cells collide with a set of points.

create_midpoint_tree(mesh, dim, entities)

squared_distance(mesh, dim, entities, points)

Compute the squared distance between a point and a mesh entity.

Classes

BoundingBoxTree(mesh, dim[, entities, padding])

Bounding box trees used in collision detection.
dolfinx.geometry.compute_closest_entity(tree: BoundingBoxTree, midpoint_tree: BoundingBoxTree, mesh: Mesh, points: numpy.ndarray) → npt.NDArray[np.int32][source]

Compute closest mesh entity to a point.

Parameters:

  • tree – bounding box tree for the entities

  • midpoint_tree – A bounding box tree with the midpoints of all the mesh entities. This is used to accelerate the search.

  • mesh – The mesh

  • points – The points to check for collision, shape=(num_points, 3)

Returns:

Mesh entity index for each point in points. Returns -1 for a point if the bounding box tree is empty.

dolfinx.geometry.compute_colliding_cells(mesh: Mesh, candidates: AdjacencyList_int32, x: numpy.ndarray)[source]

From a mesh, find which cells collide with a set of points.

Parameters:

  • mesh – The mesh

  • candidate_cells – Adjacency list of candidate colliding cells for the ith point in x

  • points – The points to check for collision shape=(num_points, 3)

Returns:

Adjacency list where the ith node is the list of entities that collide with the ith point

dolfinx.geometry.compute_collisions(*args, **kwargs)

Overloaded function.

  1. compute_collisions(tree: dolfinx::geometry::BoundingBoxTree, points: numpy.ndarray[numpy.float64]) -> dolfinx.cpp.graph.AdjacencyList_int32

  2. compute_collisions(tree0: dolfinx::geometry::BoundingBoxTree, tree1: dolfinx::geometry::BoundingBoxTree) -> numpy.ndarray[numpy.int32]

dolfinx.geometry.compute_distance_gjk(p: numpy.ndarray[numpy.float64], q: numpy.ndarray[numpy.float64]) → numpy.ndarray[numpy.float64]
dolfinx.geometry.create_midpoint_tree(mesh: Mesh, dim: int, entities: numpy.ndarray)[source]
dolfinx.geometry.squared_distance(mesh: Mesh, dim: int, entities: List[int], points: numpy.ndarray)[source]

Compute the squared distance between a point and a mesh entity.

The distance is computed between the ith input points and the ith input entity.

Parameters:

  • mesh – Mesh containing the entities

  • dim – The topological dimension of the mesh entities

  • entities – Indices of the mesh entities (local to process)

  • points – Set points from which to computed the shortest distance (shape=(num_points, 3))

Returns:

Squared shortest distance from points[i] to entities[i]